Results 1 to 10 of about 5,965 (204)

On the Laplacian spectrum of k-symmetric graphs

Discrete Mathematics
For some positive integer $k$, if the finite cyclic group $\mathbb{Z}_k$ can act freely on a graph $G$, then we say that $G$ is $k$-symmetric. In 1985, Faria showed that the multiplicity of Laplacian eigenvalue 1 is greater than or equal to the difference between the number of pendant vertices and the number of quasi-pendant vertices.
Sunyo Moon, Hyungkee Yoo
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A New Like Quantity Based on “Estrada Index”

Journal of Inequalities and Applications, 2010
We first define a new Laplacian spectrum based on Estrada index, namely, Laplacian Estrada-like invariant, LEEL, and two new Estrada index-like quantities, denoted by S and EEX, respectively, that are generalized versions of the Estrada index. After that,
A. Dilek Güngör
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Modified absolute value cumulating spectrum sensing algorithm in cognitive radio

Dianxin kexue, 2017
Absolute value cumulating (AVC) algorithm is a common spectrum sensing method in Laplacian noise (LED) surroundings,however,the ‘spikes or outliers' in Laplacian noise can't be fully smoothed,which results in bad detection performance.Aiming at this ...
Zhiyong HE
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On the Adjacency, Laplacian, and Signless Laplacian Spectrum of Coalescence of Complete Graphs

Journal of Mathematics, 2016
Coalescence as one of the operations on a pair of graphs is significant due to its simple form of chromatic polynomial. The adjacency matrix, Laplacian matrix, and signless Laplacian matrix are common matrices usually considered for discussion under ...
S. R. Jog, Raju Kotambari
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Laplacians and spectrum for singular foliations

Chinese Annals of Mathematics, Series B, 2014
The author surveys \textit{A. Connes}' results [Lect. Notes Math. 725, 19--143 (1979; Zbl 0412.46053)] on the longitudinal Laplace operator along a (regular) foliation and its spectrum (Theorems 3.1 and 3.2), and discuss their generalization to any singular foliation (i.e., leaves may have non-constant dimension) on a compact manifold.
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The Laplacian spectrum of a graph

Computers & Mathematics with Applications, 2004
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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Laplacian Spectrum and Domination in Trees

15 pages, 4 ...
Rajendraprasad, Deepak, Sankaranarayanan, Durga R.   +1 more
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The essential spectrum of the Laplacian

, 2012
In this article we prove a generalization of Weyl's criterion for the essential spectrum of a self-adjoint operator on a Hilbert space. We then apply this criterion to the Laplacian on functions over open manifolds and get new results for its essential spectrum.
Charalambous, Nelia, Lu, Zhiqin
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On the spectrum of nondegenerate magnetic Laplacians

Analysis & PDE
We consider a compact Riemannian manifold with a Hermitian line bundle whose curvature is non degenerate. Under a general condition, the Laplacian acting on high tensor powers of the bundle exhibits gaps and clusters of eigenvalues. We prove that for each cluster, the number of eigenvalues that it contains, is given by a Riemann-Roch number.
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Spectral Decomposition of the Weinstein Laplacian and Its Application to the Associated Heat Transform

International Journal of Mathematics and Mathematical Sciences
For the Weinstein Laplacian considered on the Hilbert space which makes it a self-adjoint operator, the Von Neumann spectral decomposition is given. As applications, a new integral representation for the Weinstein heat kernel is given. Also, it is proved
Abdelilah El Mourni, Nour Eddine Askour, Imane El Yazidi   +2 more
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